Isolate a for :
a - 2 b = 9
Add 2 b to both sides
a = 9 + 2 b
a = 2 b + 9
Put this value in equation:
2 a + 3 b = 4
2 ( 2 b + 9 ) + 3 b = 4
4 b + 18 + 3 b = 4
7 b + 18 = 4
Subtract 18 to both sides
7 b = - 14
b = - 14 / 7
b = - 2
Put this value in equation:
a - 2 b = 9
a - 2 ( - 2 ) = 9
a + 4 = 9
Subtract 4 to both sides
a = 5
The solutions to the system of equations are:
a = 5 , b = - 2
Solve this equation using substitution method a-2b=9 2a+3b=4
1 answer